Apple Aperture doesn’t support the Sony A850. But Charles made a free APP for you!
As you know even the new Aperture 3 version doesn’t support the Sony A850 RAW files.
The good news is that Charles Axel Pauwels made a FREE application which allows you to open the Sony A850 files with Aperzure. More infos here: http://capauwels.com/aperture-converters.html
Well done Charles!